The present invention relates to a portable boring--welding machine, of the type used to restore the original dimensions of holes or seats for knuckle pins, rotation bushings, etc., on machines or machine parts, without having to transport the part to be machined to the workshop and without positioning the part on machine tools.
Machines of this type are already known on the market. The Applicant has, for many years, manufactured and sold a boring machine, marketed with the "bimotor plus" trademark, in which the tool axle/shaft and the torch axle/shaft are driven by two different motors or drive units, specifically dedicated to driving one (at high speed) and the other (at low speed). The two motors, or drive units, are connected, with different timing, to a unit which transmits the motion to the shafts. Said unit is supported inside the self-supporting machine structure. A third motor, or drive unit, is envisaged for obtaining an axial movement of the tool and torch axles/shafts.
In the known machines, the three drive units, as described above, are housed in a box-shaped part of the machine, connected to the self-supporting structure. This box is shaped in such a way that it has, or may be fitted with, a handle for manual transportation of the machine.
The use of three motors and the relative transmissions means that the dimensions of the above-mentioned box are significant and the machine heavy. Since it must be transported manually, it should, instead, be functional and at the same time very light.